A solenoid valve usually has a coil body, a magnet core, an armature with armature guide and a yoke. Protection classes for electromagnetic devices are defined in DIN VDE 0580. An electromagnetic device in which the protection against dangerous body currents is not based solely on the basic insulation is classified in Protection Class 1. In the DIN specification for this protection class it is stated that the protection in the event of a fault must be provided in such a way that conductive magnet parts which are live in the event of a fault are connected to the protective conductor or to the conductive construction parts which are connected to the protective conductor.
In the known solenoid valves described above, the protective conductor is connected directly to the yoke of the solenoid valve by way of a rivet nut. The armature guide is connected to the yoke by way of the magnet core and a metal lock nut, and a high tightening torque must be ensured for secured contacting. If the fixing is by means of a plastic nut, the pretension due to the flow of the plastic abates with time, so that the connection becomes unreliable.
The object of the invention, therefore, is to fmd a new solution so that magnet parts which become live in the event of a fault are connected to the protective conductor or to the conductive construction parts connected to the protective conductor.